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#include <iostream>
#include <algorithm>

#define ll long long

using namespace std;

ll tab[1000005];

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    ll n; cin>>n;
    ll sum=0, one=0;
    for (int i=1; i<=n; i++)
    {
        cin>>tab[i];
        sum+=tab[i];
        if (tab[i]==1) one++;
    }
    if (sum<=(2*n-2))
    {
        cout<<0<<"\n";
        cout<<2<<"\n";
        cout<<1<<" "<<2<<"\n";
    }
    if (sum>(2*n-2))
    {
        if (one==0) cout<<2<<"\n";
        if (one==1) cout<<1<<"\n";
        if (one>=2) cout<<0<<"\n";
        cout<<2<<"\n";
        cout<<1<<" "<<2<<"\n";
    }
}